Vemork is the second plant in the Rjukan string and the largest of the five.

Vemork is the second plant in the Rjukan string and the largest of the five. The old Vemork power plant was completed in 1911 and was the world's largest hydropower station at that time. The old plant is now preserved and houses the Norwegian Industrial Workers Museum. The new Vemork power station opened in 1971 and is located in the mountains inside the old one. The plant uses a water drop of 300 meters and produces electricity from two Francis turbines.